. >> you said you'd cut the deficit in half. it's four years later, we still have trillion-dollar deficit. >> the way we do is for additional cut, we ask for a dollar of additional revenue, paid for, as i indicated earlier, by asking those of us who have done very well in this country to contribute a little bit more to reduce the deficit. >> reporter: the president insisted romney would spend $5 trillion on tax breaks favoring the wealthy. >> math, common sense and our history shows us that's not a recipe for job growth. >> everything he just said about my tax plan is inaccurate. >> reporter: they clashed on wall street, whether banks should be too big to fail, and medicare. >> cutting $716 billion from medicare to be able to balance the additional cost of obama care is, in my opinion, a mistake. >> if you repeal obama care, and i have become fond of this term, obama care, if you repeal it, what happens is those seniors right away are going to be paying $600 more in prescription care. >> reporter: the fiercest exchange over heal